Amb. Mark Andrew Green (ret.) became President & CEO of ONE in May 2026, bringing decades of experience in public service, diplomacy, development, and advocacy.
But titles only tell part of the story.
From teaching in a village in Kenya to serving as U.S. Ambassador to Tanzania, from helping advance landmark global health initiatives to leading some of the world’s most influential development institutions, Mark’s career has been shaped by a simple belief: everyone deserves the opportunity to build a better future.
We asked Mark about his journey, what brought him to ONE, and why he’s optimistic about what’s ahead. Here’s what you need to know:
Who is Mark Green?
Mark Green has spent much of his career working at the intersection of public service, development, and diplomacy.
Before joining ONE, he served as a U.S. Congressman, U.S. Ambassador to Tanzania, Administrator of USAID, President of the International Republican Institute, Executive Director of the McCain Institute, and President of the Wilson Center.
But while those roles span different sectors and continents, they have all been driven by a common goal: helping people and countries build the tools they need to thrive.
What inspired his commitment to international development?
Mark traces many of his core beliefs to an experience early in his career, when he taught in a village in Kenya.
There, he met students who were determined to create better futures for themselves and their communities despite having far fewer opportunities than many young people elsewhere in the world.
That experience helped shape his belief that development should be about creating opportunity, expanding choice, and helping countries achieve self-reliance.
That drive to have a chance, to have a seat at the table, to lead their own future has driven everything that I’ve done.”
How did Mark Green first get involved with ONE?
Mark’s relationship with ONE goes back more than two decades.
As a member of Congress, he worked closely with ONE and its partners to advance initiatives including PEPFAR, the President’s Malaria Initiative, the Millennium Challenge Corporation, and support for the Global Fund.
One of his earliest memories of the organization is an unexpected backstage conversation with ONE co-founder Bono during a campaign stop in Wisconsin—a meeting that helped spark a partnership that would continue throughout his career.
“Quite frankly, I didn’t know it at the time, but that really was an important spark in my career.”
Why did he choose to lead ONE now?
Mark believes the world is at a crossroads moment.
Many of the assumptions that shaped development over the last several decades are changing. At the same time, Africa’s role in the global economy is growing rapidly, creating new opportunities for partnership, investment, and shared prosperity.
He joined ONE because he believes the organization is uniquely positioned to help shape that next chapter.
“We are at a crossroads moment. The old systems are falling away – which means a new opportunity for a new framework, a new approach, an equal partnership with Africa that not only lifts Africa, but helps lift the world. ONE can help shape this moment.”
What does Mark think people misunderstand about Africa?
One misconception he encounters frequently is the idea that African leaders want aid.
In his experience, leaders across the continent are focused on something much bigger: opportunity.
They want stronger economies, greater investment, more jobs, and the ability to create lasting prosperity. Aid can play an important role, but only when it helps build the foundation for long-term growth and self-reliance.
“They’re looking for opportunities, and done right, aid can help them get there.”
Why is he optimistic about Africa’s future?
The answer is simple: young people.
Whether he’s meeting entrepreneurs, students, health workers, or community leaders, Mark sees extraordinary ambition, creativity, and determination across the continent.
He believes Africa’s young people will help shape the future not only of Africa, but of the world.
“Young people have big ideas, big dreams, big aspirations. They’re simply looking for people to give them a chance.”
What issue does he wish more people understood?
Health.
Mark believes access to healthcare is both a moral imperative and a foundation for economic growth.
At ONE, one of the core beliefs is that where you’re born should not determine whether you live. Healthier communities are more resilient, more productive, and better positioned to create opportunity for future generations.
For Mark, investing in health is not only the right thing to do—it’s one of the smartest investments societies can make.
What might people be surprised to learn about him?
Long before he was a congressman, ambassador, or CEO, Mark was a teacher in Kenya.
In fact, during a recent trip as ONE’s new CEO, he returned to Kisumu—the same place where, years earlier, he was treated for both typhoid and malaria while living and working in the country.
The experience gave him a firsthand understanding of why access to healthcare matters and reinforced a lesson that has stayed with him throughout his career: talent is universal, even when opportunity is not.
What is his message to people who want to make a difference?
Start where you are.
Throughout his career, Mark has learned that lasting change rarely happens all at once. Progress often comes from persistence, partnership, and people who are willing to stay engaged even when the challenges seem daunting.
He encourages people to make their voices heard, support effective solutions, and remember that individual action still matters.
“Contact your representatives and policymakers. Let them know what matters to you, that you care, that they should care too.”
Looking Ahead
Mark is realistic about the challenges facing the world today. But he is also deeply optimistic.
He believes the future will be shaped by people who refuse to give up on the idea that progress is possible. Across Africa and around the world, he sees a generation with extraordinary talent, ambition, and determination.
As he looks ahead, he believes ONE has an opportunity to help shape a new chapter in global development—one built on partnership, accountability, investment, and African leadership.
It’s a moment of significant change. But it’s also a moment of enormous possibility.
That’s what brought Mark to ONE. And that’s what excites him most about the work ahead.
